sensor_msgs pointcloud2 color value ?

edit

Does sensor_msgs/PointCloud2 data type also contains the rgb value of the image? Currentely i'm using below code, and when i publish the converted pcl type, it also shows rgb values, how is that possible?

void 
cloud_cb (const sensor_msgs::PointCloud2ConstPtr& input)
{
    pcl::PointCloud<pcl::PointXYZRGB> output;
    pcl::fromROSMsg(*input,output);
        cout<<output.at(100,100).x<<""<<output.at(100,100).r<<endl;

    }

    int
    main (int argc, char** argv)
{
  // Initialize ROS
  ros::init (argc, argv, "training");
  ros::NodeHandle nh;

  ros::Subscriber sub = nh.subscribe<sensor_msgs::PointCloud2> ("input", 1, cloud_cb);
  marker_pub = nh.advertise<visualization_msgs::Marker> ("visualization_marker",1);

  // Spin
  ros::spin ();
}

as i can see in the sensor_msgs/pointcloud2 documentations it shows below values:

std_msgs/Header header
uint32 height
uint32 width
sensor_msgs/PointField[] fields
bool is_bigendian
uint32 point_step
uint32 row_step
uint8[] data
bool is_dense

where data should be representing only the depth of the voxels. how is it returning rgb values when converted to pcl<xyzrgb> data type? i'm little confused, cas i didn't used this code for year.